Middle ear infections are common in young children. Suffering may be alleviated by puncturing the tympanic membrane to evacuate the fluid, a treatment known as tympanocentesis. The patient may undergo general anesthesia prior to a tympanocentesis procedure, but this is not preferred due to cost and health concerns. As a preferable alternative, the tympanic membrane can be locally anesthetized with an iontophoresis procedure. Thus, the patient may be treated while awake. Devices and methods for locally anesthetizing the tympanic membrane are disclosed in co-assigned patent applications U.S. Ser. No. 11/962,063 (now U.S. Pat. No. 8,192,420), U.S. Ser. No. 11/749,729 (published as U.S. Pub. No. 2008/0262510), now U.S. Pat. No. 9,387,124, issued Jul. 12, 2016), and U.S. 61/085,360, the entireties of which are incorporated by reference herein. Figure 1A shows a view of an outer ear. The outer ear includes a major element known as the Auricle or Pinna 100. The outer ear serves as a funnel for directing sounds into the internal portions of the ear. The major physical features of the ear include the Lobule 102, Concha 104, Athelix 106, Helix 108, Scapha 110, Triangular fossa 112, Externam acoustic meatus 114, Tragus 116, and Antitragus 118.
FIG. 1B shows a cross-section of the inner and outer portions of the ear. The pinna 100 is shown connected to the External auditory meatus 118, or ear canal. The ear canal 118 is shown as a relatively straight passage, but is often a tortuous passageway. The ear canal 118 is connected to the middle ear 120, which includes the ear drum 122. The middle ear 120 in turn is connected to the internal ear 124. When the middle ear 120 becomes infected, fluid swells inside the ear drum 122. Fluid expansion causes extreme pain to one with a middle ear infection.
Fluid in the middle ear is commonly known as serous otitis media or “effusion”. Effusion is normally drained through the tympanocentesis procedure. However, effusion may thicken and thus be difficult to remove or drain. Thickening of effusion is common with patients who suffer from chronic ear infections. Accordingly, a tympanocentesis procedure may not be effective in patients with lodged or thickened effusion.
Tympanocentesis procedures, which implement iontophoresis, often require iontophoresis fluid to be evacuated before the tympanic membrane is punctured. Evacuation of fluid is commonly performed through low pressure suction via a syringe or suction cannula. Fluid evacuation is often a painful and uncomfortable process because large amounts of noise are created by fluid cavitation. Thus, fluid evacuation by suction may cause pain and emotional discomfort which may prevent the completion of the tympanocentesis procedure. It should be noted that many patients are young, 5 and under, and also have endured many hours or days of a painful ear infection, and thus may be uncooperative and difficult to treat. Fluid may also be removed by swabbing the ear with an absorbent material, however this can be irritating to the patient and ineffective as well. Swabbing also requires the patient to vigorously shake their head side to side, which many young patients refuse to comply with.